package com.xu.readWriteLock;

import java.util.Random;
import java.util.WeakHashMap;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

/**
 * @author xudenghui
 * @create 2021-10-13 15:46
 **/
public class ReadWriteLockDemo {
    private static Lock lock = new ReentrantLock();
    private static ReentrantReadWriteLock readWriteLock = new ReentrantReadWriteLock();
    private static Lock readLock = readWriteLock.readLock();
    private static Lock writeLock = readWriteLock.writeLock();
    private int value;


    public Object handleRead(Lock lock) throws InterruptedException {
        try {
            lock.lock();
            Thread.sleep(1000);
            return value;
        } finally {
            lock.unlock();
        }
    }

    public void handleWrite(Lock lock,int index) throws InterruptedException {
        try {
            lock.lock();
            Thread.sleep(1000);
             value = index;
        } finally {
            lock.unlock();
        }
    }


    public static void main(String[] args) {
        final  ReadWriteLockDemo demo = new ReadWriteLockDemo();

        Runnable readRunnale = new Runnable() {
            @Override
            public void run() {
                try {
                    demo.handleRead(readLock);
                   // demo.handleRead(lock);
                }catch (InterruptedException e){
                    e.printStackTrace();
                }
            }
        };


        Runnable writeRunnable = new Runnable() {
            @Override
            public void run() {
                try {
                    demo.handleWrite(writeLock, new Random().nextInt());
                }catch (InterruptedException e){
                    e.printStackTrace();
                }
            }
        };

        for (int i = 0;i<18;i++){
            new Thread(readRunnale).start();
        }

        for (int i = 0;i<18;i++){
            new Thread(writeRunnable).start();
        }
    }
}
